Crosswind sensing from optical-turbulence-induced fluctuations measured by a video camera

We present a novel method for remote sensing of crosswind using a passive imaging device, such as a video recorder. The method is based on spatial and temporal correlations of the intensity fluctuations of a naturally illuminated scene induced by atmospheric turbulence. Adaptable spatial filtering, taking into account variations of the dominant spatial scales of the turbulence (due to changes in meteorological conditions, such as turbulence strength, or imaging device performance, such as frame rate or spatial resolution), is incorporated into this method. Experimental comparison with independent wind measurement using anemometers shows good agreement.     

A unified texture model based on a 2-D Wold-like decomposition

A unified texture model that is applicable to a wide variety of texture types found in natural images is presented. This model leads to the derivation of texture analysis and synthesis algorithms designed to estimate the texture parameters and to reconstruct the original texture field from these parameters. The texture field is assumed to be a realization of a regular homogeneous random field, which is characterized in general by a mixed spectral distribution. The texture field is orthogonally decomposed into a purely indeterministic component and a deterministic component. The deterministic component is further orthogonally decomposed into a harmonic component, and a generalized-evanescent component. Both analytical and experimental results show that the deterministic components should be parameterized separately from the purely indeterministic component. The model is very efficient in terms of the number of parameters required to faithfully represent textures. Reconstructed textures are practically indistinguishable from the originals     

Review of Sub-Nanosecond Time-Interval Measurements

A review of time-interval measurements in the sub-nanosecond regime is presented and the various methods are compared as to their precision, stability, resolution, and other essential parameters. Calibration methods, stabilization, and correction for time walk are also discussed.     

Partial diffusion reactions and the associated volume changes in thermally exposed Au-Al ball bonds

Thermal exposure of Au-Al ball bonds results in the transformation of Au-Al phases across and lateral to the ball bond that affects their service life. The phase transformations across and lateral to the Au-Al ball bond were described by partial reactions at each of the interphase boundaries. Based on a model for the mass distribution of Au from the Au phase or the Au-rich phases towards the Al phase or the Al-rich phases, volume changes associated with the partial reactions were calculated. Except for the Au₄Al and AuAl₂ phases, theoretical analysis showed that the growth of all the Au-Al phases across the ball bond results in volumetric shrinkage. The growth of the Au-Al phases across the bond is restricted due to the limited bonded Al metallization available to take part in the interdiffusion reactions. The supply limitation of the bonded metallization gives rise to reverse transformations that result in the formation of the Au₄Al phase across the entire reaction zone across the ball bond. Except for the AuAl₂ phase, theoretical analysis showed that the reverse transformation of all the Au-Al phases across the ball bond is associated with minimal volume change. A “Criterion for Inward Lateral Growth” that governs the growth of Au-Al phases laterally into the ball bond was developed. Theoretical analysis showed that except for AuAl₂, the lateral growth of all the Au-Al phases results in volumetric shrinkage. The lateral phase transformations are essentially reverse transformations due to no-supply of Au. Theoretical analysis showed that all the lateral reverse transformations also result in volumetric shrinkage.     

The Cramer-Rao lower bound for signals with constant amplitude andpolynomial phase

The authors derive the Cramer-Rao lower bound (CRLB) for complex signals with constant amplitude and polynomial phase, measured in additive Gaussian white noise. The exact bound requires numerical inversion of an ill-conditioned matrix, while its O(N ^-1) approximation is free of matrix inversion. The approximation is tested for several typical parameter values and is found to be excellent in most cases. The formulas derived are of practical value in several radar applications, such as electronic intelligence systems (ELINT) for special pulse-compression radars, and motion estimation from Doppler measurements. Consequently, it is of interest to analyze the best possible performance of potential estimators of the phase coefficients, as a function of signal parameters, the signal-to-noise ratio, the sampling rate, and the number of measurements. This analysis is carried out     

Projection-based approach to image analysis: pattern recognitionand representation in the position-orientation space

A method for image analysis, based on the formalism of functional analysis is proposed. This approach, which is employed for pattern recognition in the combined position-orientation space, is motivated by a variety of neurophysiological findings that emphasize the importance of the orientation feature in visual image processing and analysis. The approach is applied to the so-called Glass patterns, which are special cases of images characterized uniquely by their orientational feature of local correlations between pairs of corresponding dots. The approach can be of interest in the analysis of optical flow     

Integration of mechanical testing with automated parts handling in a production environment

With the emphasis on zero defects, 100% inspection is becoming a norm in manufacturing industry. In addition to dimensional and functional tests, particular mechanical tests are conducted by applying a load-deformation cycle on a component/assembly. Traditional off-line techniques, using Instron-like test machines, are not suitable for 100% inspection. Automated parts handling, using devices such as robots, is being used increasingly in production lines. The present paper examines the possibility of conducting mechanical tests with industrial robots, used for parts handling. These proposals are based on the authors' research in the area of fabric testing using robotics. This paper extends these into the wider arena of parts handling.     

Pseudorabies in a dog

Pseudorabies was diagnosed in a 5-year-old female crossbred dog by histologic examination and virus isolation. The clinical signs were depression, salivation, head pressing, and emesis. There were no gross pathologic findings. The microscopic findings in the brain stem consisted of mononuclear cell infiltrates in the leptomeninges, subarachnoid space, and neuropil. In addition, there were mononuclear cell perivascular cuffs, focal areas of gliosis, neuronal degeneration, and acidophilic intranuclear inclusions in neurons and astrocytes. Other microscopic findings were edema of lungs and fatty change in the liver. The virus was isolated from the brain and tonsils and identified by fluorescent antibody technique. Pseudorabies virus was isolated from pigs on the farm.