Abstract: The method of reducing contamination of electrical signals recorded in the presence of repeated interference contamination comprises obtaining an electrical signal recorded in the presence of a contaminating signal, and detecting a timing signal that occurs at a fixed time point during the electrical signal relative to the onset of the contaminating signal. The electrical signal is digitized, wherein the digitizing begins with the timing signal. A plurality of digitized electrical signals is analyzed, wherein the electrical signals are synchronized with respect to the timing signal, to obtain an estimated contaminating signal that is subtracted from the digitized electrical signal. This method can be used with electrophysiological signals, such as EEG, ECG, EMG and galvanic skin response, and for elimination of noise associated with concurrently used methods such as MRI. The method of noise reduction is applicable to recordings of other electrical signals, including audio recordings.

Abstract: An invention is provided for concealing an object. The invention includes a plurality of electromagnetic radiation sources that generate an electromagnetic radiation spectrum, and a controller in communication with the plurality of electromagnetic radiation sources. The controller includes logic that compares the electromagnetic radiation spectrum generated from the plurality of electromagnetic radiation sources with an electromagnetic radiation spectrum from an environment surrounding the object. In operation, the controller adjusts the plurality of electromagnetic radiation sources to generate an electromagnetic radiation spectrum that matches the electromagnetic radiation spectrum of the environment surrounding the object.