Abstract: An active noise cancellation controller for performing noise attenuation in a system over a predetermined frequency rang. The controller comprises several components: a first input for a reference signal indicative of a noise level; a second input for receiving an error signal indicative of a remnant noise level; an output for providing a noise cancellation signal; a fixed feedback controller for processing the error signal; a fixed feed-forward controller for processing the reference signal; and an adaptive feed-forward controller having a digital adaptive finite impulse response filter arranged for operation on the reference signal the error signal.

Abstract: A method for obtaining coefficients for a non-adaptive controller for use in an active noise control system, the method comprising capturing experimental data from a target system to characterise the plant of the target system; and implementing an adaptive algorithm to compute the coefficients in dependence on the experimental data.

Abstract: An active noise cancellation controller for performing noise attenuation in a system over a predetermined frequency range, the active noise cancellation controller comprising: a first input for receiving a reference signal indicative of a noise level; a second input for receiving an error signal indicative of a remnant noise level; an output for providing a noise cancellation signal to a system in which noise attenuation is to be performed; a fixed feedback controller having a fixed infinite impulse response filter arranged for operation on an error signal received at the second input; a fixed feedforward controller having a fixed infinite impulse response filter arranged for operation on a reference signal received at the first input; and an adaptive feedforward controller having a digital adaptive finite impulse response filter arranged for operation on a reference signal received at the first input and on an error signal received at the second input, the coefficients of the digital adaptive filter being de

Abstract: Acoustic shock is reduced by attenuating an input signal based on tones detected through frequency domain analysis. The spectrum of the input signal is obtained. A relative energy signal includes a plurality of relative energy elements, each representing the relative energy in a corresponding frequency bin of the input signal spectrum. A difference signal includes a plurality of difference elements, each representing a difference between a corresponding frequency bin value and an adjacent frequency bin value. A plurality of detection signals are determined, each detecting the presence of a sound element in the input signal based on at least one of the relative energy signal and the difference signal. The detection signals are combined to produce an attenuation signal for attenuating the input signal.

Abstract: Acoustic shock is reduced by attenuating an input signal based on tones detected through frequency domain analysis. The spectrum of the input signal is obtained. A relative energy signal includes a plurality of relative energy elements, each representing the relative energy in a corresponding frequency bin of the input signal spectrum. A difference signal includes a plurality of difference elements, each representing a difference between a corresponding frequency bin value and an adjacent frequency bin value. A plurality of detection signals are determined, each detecting the presence of a sound element in the input signal based on at least one of the relative energy signal and the difference signal. The detection signals are combined to produce an attenuation signal for attenuating the input signal.

Abstract: A composition, and methods for its preparation and use, for the topical treatment of areas of a human body afflicted with arthritis and muscular pain, the composition comprising extracts obtained from branches and leaves collected from mimosa and capsicum plants. The present invention is heated and used in the form of hot compresses and hot baths to treat small afflicted areas and large afflicted areas, respectively. Applications may include, but are not limited to, use in eliminating the pain, swelling, and numbness experienced by people afflicted with arthritis and similar medical conditions.