Tracking in a space variant active vision system

Without the ability to foveate on and maintain foveation, active vision for applications such as surveillance, object recognition and object tracking are difficult to build. Although foveation in cartesian coordinates is being actively pursued by many, multi-resolution high accuracy foveation in log polar space has not been given much attention. This paper addresses the use of foveation to track a single object as well as multiple objects for a simulated space variant active vision system. Complex logarithmic mapping is chosen firstly because it provides high resolution and wide angle viewing. Secondly, the spatially variant structure of log polar space leads to an object increasing in size as it moves towards the fovea. This is important as we know which object is closer to the fovea at any instant in time.<br /

Leg Paralysis Inducement by Risella 17 Oil in Lucilia sericata (Meig) as Affected by Sex, Time, Application Site, and oil Volume1

Development of leg paralysis induced by Risella 17 oil on Lucilia sericata (Meig.) was found to be significantly affected by sex, time, application site, and oil volume. Male flies were noted to be mrJre susceptible than female flies. In both sexes, more were affected at a given time when a greater volume of oil was applied. The PVso (volume of oil required to induce paralytic symptoms in 50% of the treated flies) was found to be 0.13 p.l for the male flies, and 0.2 /l-l for the female flies. Their probit regression lines are: y = 4.01x + 0.57 for the male, and y = 2.64x +1 .35 for the female. The number of male flies that developed leg paralysis was dependent on the site of application. With 0.3 p. I of oil, there were about twice as many flies affected in treatment on the abdomen as compared to that on the thorax. However, no significant difference was observed between applications made dorsally and ventrally on the abdomen. Flies treated on the head and legs did not develop any paralytic symptoms. The findings suggest that there is more than one mode of action. However, the relative importance and role of any mode of action in contributing to the paralysis inducement with subsequent death, would require further and more critical investigations

Notes on the Developmental Pattern of Leg Paralysis Induced by Risella 17 oil on Lucilia sericata (Meigen)

The developmental pattern of leg paralysis in Lucilia sericata (Meig.) induced by 0.3 pi Risella 17 oil (applied topically) was observed to differ according to whether the appendages belong to the fore-, mid-, or hindlegs. In general the forelegs were least susceptible and the number of paralytic legs increased with time. By 3 days after treatment most of the affected flies had 3-4 legs paralysed. Also evident is a strong association between the type of paralytic symptoms and the kind ofappendages

Optical studies of carrier and phonon dynamics in Ga_{1-x}Mn_{x}As

We present a time-resolved optical study of the dynamics of carriers and phonons in Ga_{1-x}Mn_{x}As layers for a series of Mn and hole concentrations. While band filling is the dominant effect in transient optical absorption in low-temperature-grown (LT) GaAs, band gap renormalization effects become important with increasing Mn concentration in Ga_{1-x}Mn_{x}As, as inferred from the sign of the absorption change. We also report direct observation on lattice vibrations in Ga1-xMnxAs layers via reflective electro-optic sampling technique. The data show increasingly fast dephasing of LO phonon oscillations for samples with increasing Mn and hole concentration, which can be understood in term of phonon scattering by the holes.Comment: 13 pages, 3 figures replaced Fig.1 after finding a mistake in previous versio