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Abstract In this paper, localization using narrowband communication signals are considered in the presence of fading channels with time of arrival measurements. When narrowband signals are used for localization, due to existing hardware constraints, fading channels play a crucial role in localization accuracy. In a location estimation formulation, the Cramer–Rao lower bound for localization error is derived under different assumptions on fading coefficients. For the same level of localization accuracy, the loss in performance due to Rayleigh fading with known phase is shown to be about 5dB compared to the case with no fading. Unknown phase causes an additional 1dB loss. The maximum likelihood estimators are also derived. In an alternative distributed detection formulation, each anchor receives a noisy signal from a node with known location if the node is active. Each anchor makes a decision as to whether the node is active or not and transmits a bit to a fusion center once a decision is made. The fusion center combines all the decisions and uses a design parameter to make the final decision. We derive optimal thresholds and calculate the probabilities of false alarm and detection under different assumptions on the knowledge of channel information. Simulations corroborate our analytical results. [ABSTRACT FROM AUTHOR]

Abstract: The study of the behavior of ion-channels can provide significant information to detect metal ions and small organic molecules in solution. Discrimination of different ion-channels can be performed by extracting appropriate features from their signals and using them for classification. In this paper, we consider features extracted from the Fourier, wavelet and Walsh power spectra of the ion-channel signals. We compare the performance of all the three sets of features using support vector machines. We perform classification of signals from simulated and real ion-channels and present the results. Results obtained show that the transform domain features achieve high classification rates in addition to high sensitivity and specificity rates. [Copyright &y& Elsevier]

Abstract: The control of unstable periodic orbits (UPOs) in chaotic systems is herein investigated by applying a weighted sum of external periodic inputs. These inputs are drawn from a “generic” set of basis functions and used to stabilize different UPOs in a chaotic attractor. All parameters associated with this multi-dimensional control scheme are experimentally computed without a priori knowledge of the system, thus making it easily applicable to a wide variety of dynamical systems. The performance of this control scheme is illustrated with several well-established chaotic systems. [Copyright &y& Elsevier]