On Lyapunov stability analyses of the switching regulator/filtersystem

The stability design criteria for the fourth-order switching regulator/low-pass filter system are obtained directly from the solution to the resultant simultaneous equations for the Lyapunov matrix equation. The regulator/filter system is asymptotically stable if the values of the filter components are chosen to satisfy the derived Lyapunov stability design criterion for a given value of the switcher dynamic resistance     

Lyapunov stability designs for switching regulator/low-pass filtersystem

The second method of Lyapunov is employed to determine quantitatively accurate criteria for asymptotic stability of the fourth-order switching-regulator/low-pass filter system. Modeling the regulator as a linearized negative resistance, this analysis provides alternative stability relationships to those found in the literature and also reveals the limitations of the Routh stability criterion. Design examples are included which ensure system stability and reduce the amplitude of the filter resonant peak (audio-susceptibility constraint)     

Correction to `Lyapunov stability designs for switchingregulator/low-pass filter system'

It is noted that the results obtained in the above-titled paper (ibid., vol.25, no.5, p.602-610, Sept. 1989) are erroneous since the Lyapunov matrix equation was not solved correctly and completely. Also, erroneous conclusions resulted because a solution to the ten simultaneous equations which result from the evaluation of that equation was not obtained. These errors are corrected and the Lyapunov simultaneous equations are solved. From the design of this fourth-order system, a comparison of the Lyapunov and Routh-Hurwitz methodologies for achieving asymptotic stability is obtained. It is shown that a design per the second method of Lyapunov simplifies the stability design calculations for this higher-order system     

Detecting small moving objects using temporal hypothesis testing

This paper addresses the problem of detecting small, moving, low amplitude objects in image sequences that also contain moving nuisance objects and background noise. We formulate this problem in the context of a hypothesis testing procedure on individual pixel temporal profiles, leading to a computationally efficient statistical test. The technique assumes we have reasonable deterministic and statistical models for the temporal behavior of the background noise, target, and clutter, on a single pixel basis. Based on these models we develop a generalized likelihood ratio test (GLRT) and perfect measurement performance analysis, and present the resulting decision rule. We also propose a parameter estimation technique and compare its performance to the Cramer Rao bound (CRB). We demonstrate the effectiveness of the technique by applying the resulting algorithm to real world infrared (IR) image sequences containing targets of opportunity. The approach could also be applicable to other image sequence processing scenarios, using acquisition systems besides IR imaging, such as detection of small moving objects or structures in a biomedical or biological imaging scenario, or the detection of satellites, meteors or other celestial bodies in night sky imagery acquired using a telescope     

Gas bubble coalescence in reduced gravity conditions.

The effects of low gravity, as produced by a reduced gravity aircraft, the KC135, on the formation and coalescence of gas bubbles were examined over a range of gas-liquid ratios and with various medium constituents. These effects will influence design considerations of fermentors operating in reduced gravity conditions.     

Equivalence of the Likelihood Ratio Processor, the Maximum Signal-to-Noise Ratio Filter, and the Wiener Filter

It is shown that for the problem of detecting a nonfluctuating target in Gaussian noise, three common optimality criteria lead to identical multichannel filter designs.