Harnessing nonlinearity for linear measurements

Measurements of detector nonlinearity at 193 nm.

We have developed a measurement system based on a correlation method to characterize the nonlinearity of a detector's response over a large range of laser pulse energy. The system consists of an excimer-laser source, beam-shaping optics, a beam splitter, a monitor detector, a set of optical filters, and the detector under test. Detector nonlinearities as large as 10% or greater over an entire m...

Stochastic Resonance: Linear Response and Giant Nonlinearity

The response of a bistable noise-driven system to a weak periodic force is investigated using linear response theory (LRT) and by analogue electronic experiment. For quasi-thermal systems the response, and in particular its increase with increasing noise intensity D, are described by the fluctuation-dissipation relations. For small D the low-frequency susceptibility of the system χ(ω) has been ...

Linear Filtering and Taiwan Stock Return Nonlinearity

The results of the previous chapter demonstrate that the serial dependencies within Taiwanese stock returns that are reflected in the significant autocorrelation and nonlinearity test results of Chapter Four are not constant; rather, they shift in direction and magnitude over time, with a number of brief episodes of very strong dependencies accounting for much of the magnitude of the full sampl...

Rapid estimation of sunflower leaf area from linear measurements

Harnessing nonlinearity: predicting chaotic systems and saving energy in wireless communication.

We present a method for learning nonlinear systems, echo state networks (ESNs). ESNs employ artificial recurrent neural networks in a way that has recently been proposed independently as a learning mechanism in biological brains. The learning method is computationally efficient and easy to use. On a benchmark task of predicting a chaotic time series, accuracy is improved by a factor of 2400 ove...